The present invention relates to an arm rest for a seat assembly and in particular to an articulating arm rest which, as it is rotated from a raised stowed position alongside the seat back to a forwardly extending use position, rotates about the longitudinal axis of the arm rest. The purpose of rotating the arm rest as it is pivoted from the stowed position to the use position is to provide an arm rest in the stowed position which has a lateral dimension that is relatively thin to minimize the seat back space occupied by the arm rest. When in the use position, however, the arm rest provides a suitably wide rest platform for the arm of the seat occupant.
In designing a motor vehicle, engineers are often faced with competing design objectives. One example is the need to reduce the size and weight of a motor vehicle while at the same time providing a vehicle which gives the occupant a spacious feeling common with larger vehicles. As the width of a vehicle decreases, the space available to provide occupant seats is also reduced. This directly competes with the desire to provide large comfortable seats for the occupant.
Accordingly, it is an object of the present invention to provide an arm rest for the vehicle seat assembly which provides a solution to the competing desires to reduce the width of a vehicle while maintaining the size of the vehicle seats.
The arm rest of the present invention accomplishes this objective by rotating about the longitudinal axis of the arm rest as the arm rest is being pivoted between an upright stowed position aligned with the seat back and a forwardly extending use position. By rotating about its axis, the arm rest in the stowed position provides a relatively narrow lateral profile along the width of the seat back, providing more room for the seat back structure and cushion. When the arm rest is pivoted to a forwardly extending use position, the arm rest rotates 90.degree. about its longitudinal axis to provide a substantially wider use platform upon which the occupant can rest his/her arm.
The arm rest includes a pivot tube coupled to said seat back for pivotal motion to raise and lower the arm rest. One end of the pivot tube extends laterally from the seat back. The center portion of the pivot tube is bent approximately 90.degree. so that the opposite end of the pivot tube extends upwardly when the arm rest is stowed and forwardly in the use position. A support tube is telescopically mounted to the pivot tube for rotation about the longitudinal axis of the support tube. A drive cable extends through the tubes with one end fixed to the seat back and the other end fixed to the support tube. Upon pivoting of the arm rest between the stowed and use positions, the drive cable rotationally drives the support tube about its axis to provide the necessary rotation.
The seat assembly further includes a four bar linkage mechanism coupled to the arm rest to define a stop for retaining the arm rest at a given angle in the use position regardless of the reclined position of the seat back.
Further objects, features and advantages of the invention will become apparent from a consideration of the following description and the appended claims when taken in connection with the accompanying drawings.